In a rack and pinion gear assembly a plurality of gear teeth on the pinion cooperate with a plurality of grooves on the rack to impart transverse movement to the rack upon rotation of the pinion, such as illustrated in U.S. Pat. Nos. 3,753,378 and 3,267,763. The torque applied to the pinion to provide for rotation of the same is transmitted to the rack via the gear teeth. Generally, the gear teeth also generate a separating force tending to separate the rack from the pinion, so that a rather strong spring is required to bias the rack into engagement with the pinion. As a result, frictional forces at the engagement between the pinion and the rack oppose rotation of the pinion and movement of the rack, so that considerable effort is required to rotate the pinion.